The present invention relates to a method of fattening up ruminants such as cattle, goat, sheep and the like. More particularly it relates to a method of fattening up the ruminants which intends to induce formation of much fat cells and enhance the fattening effect, especially increase accumulation of fat between muscle fibers during the fattening period.
As a representative example of meat wherein the accumulated amount of fat between muscle fibers is increased, the so-called marbled beef wherein fat is entered into red meat like net pattern is taken and it has being used as a high-grade meat for Japanese-style meat cooking xe2x80x9cSukiyakixe2x80x9d. However, its production is to a large degree dependent upon the way in which a cattle is fattened up by feeding it with a large amount of cerials during the entire bleeding period while a great deal of labor is required such that the body of cattle is rubbed down thoroughly so as to permeate fat into meat. Moreover, some following cares are to be taken at the finishing period:
1. To give cattle pulling-motion for increase of appetite
2. Improvement in feeding it with boil-treated feed for increase of appetite
3. Increase in the feeding number with increase in the amount of feed intake
4. To prevent scours to be caused by increasing the amount of feed intake
In recent year, the effect of vitamin A on the meat quality of the fattened cattle has been examined and the reduced amount of vitamin A contained in the assorted feed has been tested for improving the meat quality. But its effect has not been identified yet.
Thus, there are some problems to be solved for fattening up cattle for marbled beef use; much labor is required during the fattening period, the meat quality is to a high degree dependent upon the blood of cattle and the management cost is expensive. And accordingly it has been desired for the breeding farmer to provide a method of fattening up efficiently cattle having a good meat quality or a high marbled meat content.
Although Japanese Patent Application Kokai (Laid-open) No. 234,551/1985 discloses a feed for pig which contains aminobutyric acid and tryptophan, there is no description about a ruminant therein.
Also, Japanese Patent Application Kokai (Laid-open) No. 219,838/1991 discloses a broiler feed for reducing the body fat wherein valine, leucine and isoleucine as amino acid components are incorporated in each amount of 0.01 to 3.00% by weight and it is known that branched chain amino acids (valine, leucine and isoleucine) have body fat-reducing effect toward broiler. Thus there are disclosed examples of giving pig and broiler amino acids as feed and it is worthy of special mention that branched chain amino acids have body fat-reducing effect. Contrary thereto, when an amino acid is orally administrated directly to a ruminant, it is degraded or incorporated by microorganisms in the rumen and is not transported to an abomasum whereafter it is digested and absorbed. For this reason, attempts have been made to administrate to the ruminant an amino acid in the form of being coated with a hydrophobic protecting substance which is stable in the rumen of the ruminant and which makes it possible to release it in the abomasum. In the prior art amino acid administration it has been applied to ruminant of a year old or over whose function as the rumen has developed. And there have been no example of amino acid administration to the neonatal ruminant whose fermenting function of the rumen has not yet developed.
An object of the present invention is to provide a simple and convenient method of fattening up a ruminant which is very effective to cause a significant increase in accumulation of fat between muscle fibers during the fattening period.
According to the present invention feed intake of the ruminant is increased and the fattening effect may be achieved during the fattening period. The nutrients are accumulated as the body fat, especially the accumulation of fat between the muscle fibers is significantly enhanced. Thus the present invention is expected to greatly contribute to the increase in the productive performance of the marbled meat.
As a result of having ardently studied to achieve the above object, we have now found that if an amino acid and/or a peptide had been orally administrated continuously or at interval to a neonatal ruminant whose fermenting function of the rumen has not developed yet, higher fattening effect may be achieved at the subsequent fattening period than control one not received any amino acid and/or peptide, and that the accumulated amount of fat between muscle fibers is increased significantly. The present invention was based on the above findings.
That is, the present invention is a method of fattening up a ruminant which comprises orally administrating an amino acid and/or a peptide continuously or at interval to a neonatal ruminant whose fermenting function of the rumen has not yet developed, thereby effecting the enhance of accumulation of fat between muscle fibers during the fattening period, and an additive for a neonatal ruminant feed which comprises an amino acid(s) and/or a peptide(s).
As an amino acid which may be used in the present invention, a glycogenic amino acid and a branched chain amino acid are preferred. Examples of the glycogenic amino acid include asparagine, aspartic acid, lysine, methionine, proline, hydroxyproline, histidine, glycine, cystine, cysteine, alanine, serine, threonine, glutamine, valine, leucine and isoleucine. Also, examples of the branched chain amino acid include valine, leucine and isoleucine. Especially, the use of the branched chain amino acid is preferable from a standpoint of increased effect with respect to the accumulation of fat between muscle fibers.
These amino acids may be ones prepared by either synthetic or fermentation process. They may also be free amino acids prepared by hydrolyzing a protein. Mixture of these amino acids may also be used. Although free amino acids prepared by hydrolyzing a protein contain other amino acids than glycogenic amino acids in some cases, a fraction containing a large amount of glycogenic amino acids may be separated by the conventional separation process such as chromatography for use in the present invention. However, the amino acid mixture containing other amino acids than glycogenic amino acids may be applied to the present invention without necessity of separating other amino acid therefrom.
The peptide may be either one prepared by a synthetic process or one prepared by hydrolyzing a protein. Among these peptides, particularly ones containing a large amount of glycogenic amino acid or branched chain amino acid as the amino acid residue are preferred. However, even if the peptide contains other amino acid residues than glycogenic amino acid and branched chain amino acid, it may be used without accompaning any problems. As the protein source for use as the raw material, vegetable protein such as soybean protein and animal proteins derived from pig and cattle may be taken.
As to molecular weight of the amino acid and peptide which may be used in the present invention, 2,000 or less is preferable, and 1,000 or less is more preferable. These amino acid and peptide may be nutritionally and biologically acceptable derivatives or salts. For example, amino acid salts such as sodium aspartate, lysine hydrochrolide, cysteine hydrochloride and the like may be taken.
The administration period of the amino acid and/or peptide is the age of neonatal ruminant whose fermenting function of the rumen in the ruminants such as cattle, goat and sheep has not yet developed. The age of neonatal ruminant whose fermenting function of the rumen has not yet developed means a period of from a day after the birth until the function of the rumen develops (the function of the rumen develops completely and thereby the fermentation therein starts and the rumination initiates with intake of solid feed such as grass). Usually, about 2 to 3 weeks from a day after the birth become the administration period.
The amount administrated of the amino acid and/or peptide may be about 1xcx9c10 g/kg of body weight per day, and preferably 1xcx9c4 g/kg of body weight per day with consideration of the effect and economical point. The total amount to be administrated of the amino acid and/or peptide per day may be given the neonatal ruminants at one stroke or in portions of 2xcx9c3 times per day. However, it is preferable to administrate them continuously at least one time a day during the period.
As to the administration method, the amino acid and/or peptide are dissolved or suspended in water, or breast or powdered milk from any sources and the resultant solution or suspension is subjected to oral administration to a neonantal ruminant. The amino acid component may be used singly or as mixture of two or more of the amino acids stated in the above. It is not necessary to use the highly purified amino acid and it may be one containing the amount required of the amino acids stated in the above. Also, other additives such as vitamins, minerals, sugars may be added depending on the necessity.
As explained in the above, the present invention provides a feed additive comprising an amino acid and/or a peptide which is effective to increase the accumulation of fat between the muscle fibers during the fattening period when they had been orally administrated to a baby ruminant whose function as the rumen has not yet developed.
The present invention is illustrated in more details with reference to the following examples.
1. Test Animal
The following 4 castrated sheep which were born and bred in the stock farm affiliated to the Faculty of Agriculture, the University of Tokyo were used for the test.
2. Amino Acid
Glycogenic amino acid: alanine, proline and glycine Branched chain amino acid: leucine, isoleucine and valine
3. Amount Administrated of Amino Acid
3 Kinds of glycogenic amino acids or 3 kinds of branched amino acids were mixed in equal amounts and orally administrated to the test sheep one time a day in the amount of 2 g per kg of the body weight in the state of being suspended in water.
4. The Period Administrated of Amino Acid
For 2 weeks after the birth:
5. The Fattening Period
Oct. 30, 1995xcx9cuntil the day of slaughter
6. Feed
As feed before the initiation of fattening, the standard feed which has a mixing ratio shown in table 1 and which has been used in the stock farm affiliated to the Faculty of Agriculture, the University of Tokyo was given the test animal twice a day with consideration of the body weight.
The fattening feed xe2x80x9cMilk and Beefxe2x80x9d [trade name, a product of National Dairy Farming Cooperatives Association(Zenrakuren)] and water were given ad libitum the test animal during the fattening period.
7. Daily Management
The health condition including occurrence of abnormality such as scours was observed every day. Any abnormality was not observed during the experimental period.
8. Items Inspected for the Carcass Were as Shown Below
Living weight
Carcass weight
Weight of fat between intestines
Weight of fat around the kidney
Weight of subcutaneous fat
Muscle weight
Bone weight
Crude fat content in the muscular tissue
Measuring Method
The longest breast muscle (M. longissimus thoracis) at 13th thoracic vertebrae was cut into a block having about 3 cm in width and stored in a refrigerator. About 5xcx9c19 g of the central part of the frozen block was cut out and dehydrated. And thereafter the crude fat was extracted with ethyl ether for assay its content.
9. Results
The test results thus obtained are summarized in table 2.
As can be seen from Table 2, although there is no significant difference in the bone weight between the amino acid administration group and the amino acid non-administration group (control group), significant increase in the living weight, the carcass weight and the fat weight is observed in the amino acid administration group and there is the marked tendency especially in the fat weight.
The administration of amino acid for 2 weeks after the birth of the sheep serves to increase the feed intake, enhance the fattening effect and accumulate the nutrients as the body fat. Although the tendency is recognized between intestines, around the kidney and the subcutaneous fat, the marked increase is recognized in the crude fat content in the longest breast muscle at 13th thoracic vertebrae.
Generally, the body fat accumulates first under the skin, in the internal organs and then between the muscle fibers. The administration of the amino acid to the baby ruminant is considered to have brought about the above result as the implantating effect.
Furthermore, in the comparison between the glycogenic amino acid and branched chain amino acid administration groups, higher effect may be achieved by the branched chain amino acid administration with respect to increase in the crude fat content in the breast muscle of 13th thoracic vertebrae.